ht can be produced by
processes to which we do not generally apply the idea of burning.
Resins, wool, silks, wood, and all kinds of earths and alkalies, are
capable of emitting light in suitable electrical conditions; so that
the surface of our earth may have been a source of light in past ages,
as it even now is,[260] near the poles and the equator, flashing its
Aurora Borealis and Aurora Australis, and sending out its belts of
Zodiacal light,[261] far into the surrounding darkness.

Schubert, quoted by Kurtz, says: "May not that polar light, which is
called the Aurora of the North, be the last glittering light of a
departed age of the world, in which the earth was inclosed in an expanse
of aerial fluid, from which, through the agency of electric magnetic
forces, streamed forth an incomparably greater degree of light,
accompanied with animating warmth, almost in a similar mode to what
still occurs in the luminous atmosphere of our sun?"

Again, the metallic bases of all the earths are highly inflammable. A
brilliant flame can be produced by the combustion of water. All the
metals can be made to flash forth lightnings, under suitable electric
and magnetic excitements. The crystals of several rocks give out light
during the process of crystallization. Thousands of miles of the earth's
surface must once have presented the lurid glow of a vast furnace full
of igneous rocks. Even now, the copper color of the moon during an
ellipse shows us that the earth is a source of light.[262] The mountains
on the surface of Venus and the moon, and the continents and oceans of
Mars, attest the existence of upheaval and subsidence, and of volcanic
fires, capable of producing such phenomena, and of course of sources of
light in those planets, such as exist on the earth. We know, then, most
certainly, that there are many other bodies capable of producing light
besides the sun. That God could command the light to shine out of
darkness, and convert the very ocean into a magnificent illumination,
the following facts clearly prove. "Capt. Bonnycastle, coming up the
Gulf of St. Lawrence, on the seventh of September, 1826, was roused by
the mate of the vessel, in great alarm, from an unusual appearance. It
was a starlight night, when suddenly the sky became overcast, in the
direction of the high land of Cornwallis County, _and an instantaneous
and intensely vivid light, resembling the Aurora, shot out of the
hitherto gloomy and dark sea_, on th